Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

Indonesian Journal of Chemistry

ijc
Website

Published by Universitas Gadjah Mada

ISSN : 14119420 EISSN : 24601578 DOI : -

Core Subject : Science, Engineering,

Chemical Engineering, Chemistry & Bioengineering Chemistry

Indonesian Journal of Chemistry is an International, peer-reviewed, open access journal that publishes original research articles, review articles, as well as short communication in all areas of chemistry including applied chemistry. The journal is accredited by The Ministry of Research, Technology and Higher Education (RISTEKDIKTI) No : 21/E/KPT/2018 (in First Rank) and indexed in Scopus since 2012. Since 2018 (Volume 18), Indonesian Journal of Chemistry publish four issues (numbers) annually (February, May, August and November).

Arjuna Subject : -

Articles 8 Documents

Search results for , issue "Vol 1, No 1 (2001)" : 8 Documents clear

The Effect of Salinity on the Release of Copper (Cu), Lead (Pb) And Zinc (Zn) from Tailing Apriani Sulu Parubak; Eko Sugiharto; Mudjiran Mudjiran
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The effects of salinity on the release of copper (Cu), lead (Pb) and zinc (Zn) in tailing sediment have been studied by stripping voltammetry. The purpose of the research is to know the effect of salinity on the release of metals with certain pH, conductivity and variety of metals. Simultaneous determination of copper, lead and zinc in tailing was done by Differential Pulse Anodic Stripping Voltammetry (DPASV) onto hanging mercury drop electrode (HMDE) and nitric acid 65% as support electrolyte. The limit of detection for this method 0.60 µg/L, 0.150 µg/L and 0.238 µg/L for copper, lead and iMc respectively. The stripping solution of 300/00 salinity with pH= 7.85, conductivity= 46.62 mS/cm gives the amounts of released metals as follows :14.867 µg/L Cu, 0.976 µg/L Pb and 6.224 µg/L Zn. These results are higher as compared with the results from 15 0/00 salinity with pH= 7.66, conductivity= 23.22 mS/cm that give released metals of Cu= 7.988 µg/L, Pb= 0.311 µg/L and Zn= 4.699 µg/L. the results from ANOVA suggest that this is due to different in salinity of the solution. It also found that the conductivity does not give any effect. It can be concluded that the higher salinity will that give higher concentration or released metals.

Effect of Residence Time of Graphitisation on Thermal Conductivity of Molded Graphite Pedy Artsanti; Yateman Arryanto; Kusnanto Kusnanto
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The effect of residence time of graphitisation on thermal conductivity of molded graphite has been examined. The examination has been conducted by varying residence time of graphitisation of molded carbon with petroleum coke as raw material and coal tar pitch. Graphitisation has been conducted by heating molded graphite at 2500 °C in argon atmosphere with residention time of 10, 30 and 90 minutes. Graphitisation degree, density, shrinking mass and porosity of molded graphite were examined and so was its thermal conductivity. The result showed that the decrease of porosity and the increase of graphitisation degree due to the increasing of residention time of graphitisation will increase the thermal conductivity of graphite. Molded graphite graphitisized with residence time for 90 minutes residention time gave thermal conductivity of 2.134 Watt/mK and graphitization degree 0.718.

Storage and Condition of Biomass Influence to Biosorption of Lead (II) and Zinc(II) by Saccharomyces cerevisiae Biomass Jasmidi Jasmidi; Eko Sugiharto; Mudjiran Mudjiran
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The influence of length and condition of Biomass Storage on the biosorption of lead and zinc that present together in a solution by Saccharomyces cerevisiae biomass were studied. In this experiment, variables of length and condition of biomass storage were examined. Concentration of lead and zinc were determined by atomic absorption spectrophotometric (AAS) using air-acetilene as atomizing flame. Loading of lead and zinc on the biomass were determined as the difference between the initial and the final concentration of lead and zinc in the solution. Biosorption of lead and zinc were influenced by condition and storage of the biomass. Storage of biomass in the room temperature for one week cause an increasing uptake. Storage for longer period result in decrease of lead and zinc uptake. Storage of biomass in a freezer up to 2 weeks increased the uptake of lead, but did not influence the uptake of zinc. Storage for longer period decreased the uptake of both of lead and zinc. For all condition the uptake of lead higher than the uptake of zinc by Saccharomyces cerevisiae.

Selectivity of an Active Natural Zeolite in Catalytic Conversion Process of Bangkirai, Kruing and Kamper Woods Biofuel to Gasoline Fraction Wega Trisunaryanti
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The selectivity of an active natural zeolite (ZAAH) in catalytic conversion process of Bangkirai, Kruing and Kamper woods biofuels has been studied. The ZAAH catalyst was prepared from a natural zeolite (ZA) treated with acids solution (1% HF and 6M HCI) and hydrothermal then calcined at 500 °C and oxidized at 400 °C under nitrogen and oxygen gas stream, respectively. Characterizations of the catalysts including Si/Al ratio and acidity were determined by atomic adsorption spectroscopy (AAS) and ammonia gas adsorption method, respectively. The conversion process was carried out in a flow reactor system at 400 °C, under N2 stream (20 mL/min). The biofuel was vaporized from the pyrolysis zone to the catalytic reactor. A liquid product was covered and analyzed by gas chromatograph (GC) and that connected with mass spectroscopy (GC-MS). The characterization results showed that the Si/AI ratio and acidity of the ZAAH were higher than that of the ZA catalyst. The GC-MS data showed that the highest product selectivity was 2,4-dimethyl heptane and 1,2-dimethyl benzene. The total product selectivity using the ZAAH catalyst (bangkirai = 68.10%; kruing = 54.76%; kamper = 50.72%) was higher than that of the ZA catalyst (bangkirai = 39.24%; kruing = 44.38%; kamper = 46.11%).

Characterization and Modification of Natural Zeolite and Its Cracking Properties on Petroleum Fraction Mukhamad Nurhadi; Wega Trisunaryanti; M Utoro Yahya; Bambang Setiaji
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

Preparation of natural zeolite catalyst consist of dealumination using acid (HF 1% (v/v), HCI 1M), steaming at calcination temperature and both treatments ware carried out. The modification of the zeolite catalyst was done by loading a small amount of chromium (3% b/b) on the zeolite by ion exchange method. Ion exchange was processed by immersing the zeolite in 0.115 M chromium nitrate solution, followed by oxidation with oxygen gas and reduction by hydrogen gas. The characterization of the zeolite catalyst by mean of Si/AI ratio, acidity, metal contents (Na, K, Ca, Fe and Cr) and surface area including pore size distribution were determined by gravimetric method, ammonia adsorption, Atomic Adsorption Spectroscopy (AAS) and nitrogen gas sorption analyzer (NOVA-1000), respectively. The result of characterization showed that dealumination process increased the Si/AI ratio, acidity and decreased the metal content. The result of cracking process showed that modification of the natural zeolite catalyst enhanced the catalysis property, it showed relatively high cracking activity of petroleum fraction and low kokass formation.

The Multielectrodes Oscillation System Studied by Irreversible Thermodynamics Eko Suhartono; Djaka Sasmita; RHA. Sahirul Alim
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

Oscillation process that occurs in a system may be formed from non linear dynamic phenomena that far from equilibrium. Mechanism of oscillation in a chemical reaction system such as Belousov-Zhabotinski (B-Z) reaction is quite complex. For that reason, in order the irreversible thermodynamics that far from equilibrium can be more easily understood, the generation of oscillation in a system is tried to be investigated in this study. In this case, the author attempts to come up at the oscillation process coming from the potential difference between the couple of Pb and PbO2 electrodes which are parallel arranged to from eight channels in the solution of sulfuric acid with certain concentrations. The measurements of potential difference from PbllPbO2 electrode, i.e., from the eight channels all together, were done by the use of an interface connected to a computer and it worked with time interval of one second for the time duration of 5 hours. The data were then automatically recorded. Non periodic waves which were resulted from all channels have wave forms which are triangular and square. Oscillation process occurred in each channel of a couple of PbIIPbO2 electrodes can be compared with the process of spreading of action potentials that occur in nerve cells.

A Kinetic Study of Aluminium(III) and Chromium(III) Adsorption by Silica Gel Chaetoceros calcitrans Biomass Immobilized on Silica Gel Indah Raya; Narsito Narsito; Bambang Rusdiarso
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The kinetics of aluminium(III) and chromium(III) adsorption in an adsorbent prepared by immobilization of Chaetoceros calcitrans biomass on silica ge has been investigated. The functional groups which were probable involved in the adsorption processes also identified. Experimentally, the adsorption was conducted by coloumn and batch method. In this work atomic adsorption spectrophotometric techniques was applied indirectly to determine of the metal ion adsorpted, and infra red spectroscopic technique was used for the identification of functional groups present in the adsorbent. The study included two parts of experiment, i.e. 1) the determination of rate of adsorption and 2) the determination of capacity and energy of adsorption. Results showed that the AI(III) and Cr(III) adsorption data fit quiet well with non linear kinetics model proposed by Langmuir-Hinshelwood giving a first order rate constant, (k1) of 8.65.10-3 min-1 for AI(III) and 9.92.10-4 min' for Cr(III) when the immobilized biomass used as the adsorbent in agreement with the activation energy calculation giving values of 1.184 kcal/mole for Al(111) and 1.877 kcal/mole for Cr (Ill). It was concluded that the adsorption of Al(III) and Cr(III) on Chaetoceros calcitrans immobilized and free Chaetoceros calcitrans adsorbents, may be classified as chemical adsorption, involving entalphi of adsorption in the range of 6-17 kcal/mole. And the infra red spectroscopic data indicated that the functional groups i.e.: carboxylate (-COO), hydroxyl (-OH) silanol (SI-OH), siloksil (SI-O-Si) and amine (NH2) are present in free Chaetoceros calcitrans biomass and silanol (Si-OH), siloksil (Si-O-Si), hydroxyl (-OH)and C-H metilene (-CH2) are present in immobilized biomass Chatoceros calcitrans, while only siloksil (Si-O-Si) and silanol (Si-OH) in silica gel.

The Intercalation of Copper into Active Carbon and Its Application as a Catalyst for n-Amylalcohol Dehydration Rusman Rusman; Iip Izul Falah; RHA. Sahirul Alim
Indonesian Journal of Chemistry Vol 1, No 1 (2001)
Publisher : Universitas Gadjah Mada

The intercalation of CuCl2 salts into active carbon and its activity as catalyst on dehydration of n-amylalcohol has been investigated. In this research, the intercalation was conducted by reacting CuCl2 powder with active carbon and Cl2 gas at 3 atm, temperature 575 °C, at various heating time. This process was then followed by the reduction in the flowing hydrogen gas. Characterization of intercalation product was conducted by gas sorption method to determine surface area, pore radius, and pore volume distribution, and atomic adsorption spectroscopy (AAS) was used to determine the content of Cu metal. The test of catalytic activity on dehydration reaction of n-amylalcohol, was carried out in a flow reactor system at various temperatures. The results showed that the surface area and total pore volume increase with the longer time of intercalation process, and followed by increasing Cu content on active carbon. It was showed further that catalyst with highest Cu content, and the largest of both of surface area and total pore volume gives the best performance.

Page 1 of 1 | Total Record : 8

Filter by Year

2001 2001

Filter By Issues

All Issue Vol 25, No 5 (2025) Vol 25, No 4 (2025) Vol 25, No 3 (2025) Vol 25, No 2 (2025) Vol 25, No 1 (2025) Vol 24, No 6 (2024) Vol 24, No 5 (2024) Vol 24, No 4 (2024) Vol 24, No 3 (2024) Vol 24, No 2 (2024) Vol 24, No 1 (2024) Vol 23, No 6 (2023) Vol 23, No 5 (2023) Vol 23, No 4 (2023) Vol 23, No 3 (2023) Vol 23, No 2 (2023) Vol 23, No 1 (2023) Vol 22, No 6 (2022) Vol 22, No 5 (2022) Vol 22, No 4 (2022) Vol 22, No 3 (2022) Vol 22, No 1 (2022) Vol 22, No 2 (2022) Vol 21, No 6 (2021) Vol 21, No 5 (2021) Vol 21, No 4 (2021) Vol 21, No 3 (2021) Vol 21, No 2 (2021) Vol 21, No 1 (2021) Vol 20, No 6 (2020) Vol 20, No 5 (2020) Vol 20, No 4 (2020) Vol 20, No 3 (2020) Vol 20, No 2 (2020) Vol 20, No 1 (2020) Vol 19, No 4 (2019) Vol 19, No 3 (2019) Vol 19, No 2 (2019) Vol 19, No 1 (2019) Vol 18, No 4 (2018) Vol 18, No 3 (2018) Vol 18, No 2 (2018) Vol 18, No 1 (2018) Vol 17, No 3 (2017) Vol 17, No 2 (2017) Vol 17, No 1 (2017) Vol 16, No 3 (2016) Vol 16, No 2 (2016) Vol 16, No 1 (2016) Vol 15, No 3 (2015) Vol 15, No 2 (2015) Vol 15, No 1 (2015) Vol 14, No 3 (2014) Vol 14, No 2 (2014) Vol 14, No 1 (2014) Vol 13, No 3 (2013) Vol 13, No 2 (2013) Vol 13, No 1 (2013) Vol 12, No 3 (2012) Vol 12, No 2 (2012) Vol 12, No 1 (2012) Vol 11, No 3 (2011) Vol 11, No 2 (2011) Vol 11, No 1 (2011) Vol 10, No 3 (2010) Vol 10, No 2 (2010) Vol 10, No 1 (2010) Vol 9, No 3 (2009) Vol 9, No 2 (2009) Vol 9, No 1 (2009) Vol 8, No 3 (2008) Vol 8, No 2 (2008) Vol 8, No 1 (2008) Vol 7, No 3 (2007) Vol 7, No 2 (2007) Vol 7, No 1 (2007) Vol 6, No 3 (2006) Vol 6, No 2 (2006) Vol 6, No 1 (2006) Vol 5, No 3 (2005) Vol 5, No 2 (2005) Vol 5, No 1 (2005) Vol 4, No 3 (2004) Vol 4, No 2 (2004) Vol 4, No 1 (2004) Vol 3, No 3 (2003) Vol 3, No 2 (2003) Vol 3, No 1 (2003) Vol 2, No 3 (2002) Vol 2, No 2 (2002) Vol 2, No 1 (2002) Vol 1, No 3 (2001) Vol 1, No 2 (2001) Vol 1, No 1 (2001) Article in press ARTICLE IN PRESS More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kab. sleman, Daerah istimewa yogyakarta INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA